Dude - I drove the Autobahns for 5 years in a BMW. When you average above 100 mph, there are a few that go by, but you don't want to be in the left-hand lane when they do. You're not built to run with the 150+ crowd. If that's where you want to run, I suggest you look for handling & stability mods before you look at tunes. 0-to-whatever can sure improve with a tune, but it's got to stick to the road. I've run mine at 130+ and it becomes "very sensitive" to wind. But having said that, she'll run 120 and under all friggin day. I'd sure like to do some running on the secondary roads in SPORT mode. I pulled up on an Audi TT this morning. Yeah, he got away, but just barely, and boy what he surprised. I didn't get the chance to see if he had the stones for a real run, but off the light, I made him sweat.
PJ's $0.02